Polymerizable compositions based on epoxides

ABSTRACT

The present invention is directed to polymerizable dental compositions containing a) 3 to 80 wt. % of cycloaliphatic epoxides; b) 0 to 80 wt. % of an epoxide or a mixture of epoxides which are different from a); c) 3 to 85 wt. % of a filer material; d) 0.01 to 25 wt. % of initiators, inhibitors and/or accelerators; e) 0 to 25 wt. % of auxiliary agents, the individual percentages of which are in relation to the total weight. The new polymerizable agents are particularly suited as dental material.

This application is the national phase under 35 U.S.C. §371 of prior PCTInternational Application No., PCT/EP97/06504, which has anInternational filing date of Nov. 21, 1997, which designated the UnitedStates of America, the entire contents of which are hereby incorporatedby reference.

The invention relates to polymerizable compositions based on epoxides,new cycloaliphatic epoxides and their use.

Methacrylate and acrylate monomers have hitherto chiefly been used inpolymerizable dental compositions.2,2-Bis[4,1-phenylenoxy(2-hydroxy-3,1-propanediyl)-methacrylic acidester]-propylidene (bis-GMA) [U.S. Pat. No. 3,066,112], described byBowen, deserves particular attention. Mixtures of this methacrylate withtriethylene glycol dimethacrylate are also used nowadays as the standardrecipe for dental plastic direct filling materials. Methacrylderivatives of diformylatedbis-(hydroxymethyl)tricyclo[5.2.1.0^(2,6)]-decane have also provedsuitable as monomers for dental composites [W. Gruber et al., DE-A-27 14538; W. Schmitt et al., DE-C-28 16 823; J. Reiners et al., EP-A-0 261520]. A great disadvantage of the known polymerizable dentalcompositions is the polymerization shrinkage which, for example whenthey are used as filling material, can cause secondary caries due to theformation of edge gaps. Furthermore, in acrylate-based dentalcompositions, the polymerization inhibition by oxygen leads to theformation of a so-called greasy layer which, for example in the case offillings, is undesirable and even harmful. Finally, acrylate-basedpolymerizable dental compositions have a low adhesion to the toothsubstance.

Although there is extensive experience with epoxides and cycloaliphaticepoxides U.S. Pat. No. 2,716,123, U.S. Pat. No. 2,750,395, U.S. Pat. No.2,863,881, U.S. Pat. No. 3,187,018), such monomers and cationicallypolymerizable compositions formulated therefrom having the propertiesnecessary for dental uses have not been commercially available at anypoint in time.

The preparation of bifunctional cycloaliphatic epoxides is alreadydescribed in patents from the 1950s (U.S. Pat. No. 2,750,395, U.S. Pat.No. 900,506, U.S. Pat. No. 907,149, U.S. Pat. No. 2,745,847, U.S. Pat.No. 2,853,499, U.S. Pat. No. 3,187,018, U.S. Pat. No. 2,863,881, U.S.Pat. No. 2,853,498). Silicon-containing cycloaliphatic epoxides havebeen described by Crivello et al. in various publications (EP-A-0 449027; J. Polym. Sci., Part A: Polym. Chem., 28 (1990) 479, ibid. 31(1993) 2563; ibid. 31 (1993) 2729; ibid. 31 (1993) 3109; ibid. 31 (1993)3121; ibid. 33 (1995) 2463). The known cycloaliphatic epoxides areessentially low molecular weight monomers which indeed have a somewhatreduced polymerization shrinkage [J. Adhes. Sci. Technol. 9 (10) 1995,1343; DE-A-4 340 949], but because of their high density of functionalgroups, do not meet the requirements (processing, physical properties)for dental uses.

Only little is known of cationically curable epoxide compositions fordental uses: The patent U.S. Pat. No. 5,556,896 describesepoxide-containing compositions which must necessarily comprisespiroorthocarbonates as shrinkage-compensating monomers. The companyCiba described in 1958, in the patent AT-A-204 687, epoxide dentalcompositions based on bisphenol A which were cured by means of Lewisacid catalysts. The long curing time and the low mechanical strength andlong-term stability were problematic in these formulations. Thecompanies Minnesota Mining and Manufacturing Company and Wictorin et al.describe in patents (WO 96/13538 and WO 95/30402) cationically curableepoxy mixtures, preferably with 3,4-epoxycyclohexyl-methyl3,4-epoxycyclohexanecarboxylate or bis(3,4-epoxycyclohexyl adipate).This type of epoxide is highly cytotoxic and in vitro tests showed forthese monomers mutagenic properties, which are undesirable in dentaluse.

The object of the present invention is to provide polymerizablecompositions which, by comparison with the known compositions, inaddition to a high reactivity and the necessary mechanical properties,have a low volume shrinkage and have no mutagenic and only mildcytotoxic properties.

According to the invention, this object is achieved by polymerizablecompositions comprising

(a) 3 to 80 wt. %, preferably 3 to 75 wt. %, and in particular 5 to 70wt. % of an epoxide or a mixture of epoxides of the general formula:

 in which, for type A:

if n=2

Z denotes a cycloaliphatic or aromatic radical having 1 to 22,preferably 1 to 18 C atoms or a combination of these radicals, whereinone or more C atoms can be replaced by O, C═O, —O(C═O)—, SiR₂ and/or NR,or an aliphatic radical having 0 to 22, preferably 1 to 18 C atoms,wherein one or more C atoms can be replaced by O, C═O, —O(C═O)—, NR orSiR₂, wherein at least one C atom must be replaced by SiR₂, and whereinR is an aliphatic radical having 1 to 7 C atoms, wherein one or more Catoms can be replaced by O, C═O and/or —O(C═O)—.

if n>2

Z denotes an aliphatic, cycloaliphatic or aromatic radical having 0 to22, preferably 0 to 18 C atoms or a combination of these radicals,wherein one or more C atoms can be replaced by O, C═O, —O(C═O)—, SiR₂and/or NR and wherein R is an aliphatic radical having 1 to 7 C atoms,wherein one or more C atoms can be replaced by O, C═O and/or —O(C═O)—,

and in which, for type B:

Z denotes an aliphatic, cycloaliphatic or aromatic radical having 0 to22, preferably 0 to 18 C atoms or a combination of these radicals,wherein one or more C atoms can be replaced by O, C═O, —O(C═O)—, SiR₂and/or NR and wherein R is an aliphatic radical having 1 to 7 C atoms,wherein one or more C atoms can be replaced by O, C═O and/or —O(C═O)—,

and in which, for type A and type B:

A denotes an aliphatic, cycloaliphatic or aromatic radical having 1 to18, preferably 1 to 15 C atoms or a combination of these radicals,wherein one or more C atoms can be replaced by O, C═O, —O(C═O)—, SiR₂and/or NR, wherein R is an aliphatic radical having 1 to 7 C atoms, inwhich one or more C atoms can be replaced by O, C═O and/or —O(C═O)—,

B₁, B₂, D and E independently of one another denote an H atom or analiphatic radical having 1 to 9, preferably 1 to 7 C atoms, wherein oneor more C atoms can be replaced by O, C═O, —O(C═O)—, SiR₂ and/or NR,wherein R is an aliphatic radical having 1 to 7 C atoms, in which one ormore C atoms can be replaced by O, C═O and/or —O(C═O)—,

n denotes 2-7, preferably 2-5, in particular 2-4,

m denotes 1-10, preferably 1-7, in particular 1-5,

p denotes 1-5, preferably 1-4, in particular 1 or 2,

q denotes 1-5, preferably 1-4, in particular 1 or 2, and

x denotes CH₂, S or O,

(b) 0 to 80, preferably 0 to 70 wt. % of an epoxide or a mixture ofepoxides which differ from (a),

(c) 3 to 85, preferably 5 to 75 wt. % of fillers,

(d) 0.01 to 25, preferably 0.01 to 20 wt. % of initiators, retardantsand/or accelerators,

(e) 0 to 25, preferably 0 to 20 wt. % of auxiliaries, the percentagedata in each case being based on the total weight of the composition.

Preferred compositions according to the invention comprise, as component(a), one or more of the epoxides listed below:

i)2,2-bis[4,1-phenylenoxy-3,1-propanediyl-3,4-epoxy-cyclohexylcarboxylicacid ester]propylidene

ii)2,2-bis[4,1-phenylenoxy-3,1-propanediyl-oxy-methanediyl-3,4-epoxycyclohexyl]propylidene

iii)2,2-bis[3,4-epoxycyclohexylmethanediyl(4,1-phenylenoxy-3,1-propylcarboxylicacid ester)]propylidene

iv)2,2-bis[4,1-phenylenoxy-3,1-propanediyl-1,1,3,3-tetramethyldisiloxanyl-1,2-ethanediyl-3,4-epoxycyclohexyl]propylidene

v)2,2-bis{4,1-phenylenoxy-3,1-propanediyl-3-oxatricyclo[3.2.1.0^(2,4)]octyl-6-carboxy}propylidene

vi)2,2-bis{4,1-phenylenoxy-3,1-propanediyl-3,8-dioxatricyclo[3.2.1.0^(2,4)]octyl-6-carboxy}propylidene

vii)2,2-bis{4,1-phenylenoxy-3,1-propanediyl-[3,5,7-tris(ethanediyl-3,4-epoxycyclohexyl)-1,3,5,7-tetramethylcyclotetrasiloxanyl]}propylidene

viii) bis[methanediyl-oxy-3,1-propanediyl-3,4-epoxycyclohexylcarboxylicacid ester]tricyclo[5.2.1.0^(2,6)]decane

ix)bis[methanediyl-oxy-3,1-propanediyl-oxy-methanediyl-3,4-epoxycyclohexyl]tricyclo[5.2.1.0^(2,6)]decane

x) bis[3,4-epoxycyclohexylmethanediyl-propanecarboxylicacid-1-oxy-methanediyl]tricyclo[5.2.1.0^(2,6)]decane

xi)bis(methanediyl-oxy-3,1-propanediyl-1,1,3,3-tetramethyldisiloxanediyl-1,2-ethanediyl-3,4-epoxycyclohexyl)tricyclo[5.2.1.0^(2,6)]decane

xii)bis{methanediyl-oxy-3,1-propanediyl-3-oxatricyclo[3.2.1.0^(2,6)]octyl-6-carboxyl}tricyclo[5.2.1.0^(2,6)]decane

xiii)bis{methanediyl-oxy-3,1-propanediyl-3,8-dioxatricyclo[3.2.1.0^(2,6)]octyl-6-carboxyl}tricyclo[5.2.1.0^(2,6)]decane

xiv)bis(methanediyl-oxy-(3-propanediyl-3,5,7-tris(2,1-ethanediyl-3,4-epoxycyclohexyl)-1,3,5,7-tetramethylcyclotetrasiloxanyl)-tricyclo[5.2.1.0^(2,6)]decane

xv) 1,1,1-tris[methanediyl-oxy-methanediyl-3,4-epoxycyclohexyl]propane

xvi)1,1,1-tris[methanediyl-oxy-1,3-propanediyl-1,1,3,3-tetramethyldisiloxanediyl-1,2-ethanediyl-3,4-epoxycyclohexyl]propane

xvii)1,1,1-tris{methanediyl-3-oxatricyclo[3.2.1.0^(2,4)]octyl-6-carboxy}propane

xviii)1,1,1-tris{methanediyl-3,8-dioxatricyclo[3.2.1.0^(2,4)]octyl-6-carboxy}propane

xix)1,1,1-tris[methanediyl-oxy-3,1-propanediyl-3,5,7-tris(2,1-ethanediyl-3,4-epoxycyclohexyl)-1,3,5,7-tetramethylcyclotetrasiloxanyl]propane

xx)1,1,1-tris[methanediyl-oxy-bis(ethanediyloxy)-3,4-epoxycyclohexylcarboxylicacid ester]propane

xxi)1,1,1-tris[methanediyl-oxy-bis(ethanediyloxy)-methanediyl-3,4-epoxycyclohexyl]propane

xxii)1,1,1-tris[methanediyl-oxy-bis(ethanediyloxy)-propanediyl-1,1,3,3-tetramethyldisiloxanyl-1,2-ethanediyl-3,4-epoxycyclohexyl]propane

xxiii)1,1,1-tris{methanediyl-oxy-bis(ethanediyloxy)-3-oxatricyclo[3.2.1.0^(2,4)]octyl-6-carboxy}propane

xxiv)1,1,1-tris{methanediyl-oxy-bis(ethanediyloxy)-3,8-dioxatricyclo[3.2.1.0^(2,4)]octyl-6-carboxy}propane

xxv)1,1,1-tris[methanediyl-oxy-bis(ethanediyloxy)-propanediyl-3,5,7-tris(2,1-ethanediyl-3,4-epoxycyclohexyl)-1,3,5,7-tetramethylcyclotetrasiloxanyl]propane

xxvi)α,ω-bis[3,4-epoxycyclohexylethanediyl-1,1,3,3-tetramethyldisiloxanyl-3,1-propanediyl]polytetrahydrofuran

xxvii)α,ω-bis{3-oxatricyclo[3.2.1.0^(2,4)]octyl-6-carboxy}polytetrahydrofuran

xxviii)α,ω-bis{3,8-dioxatricyclo[3.2.1.0.^(2,4)]octyl-6-carboxy}polytetrahydrofuran

xxix)α,ω-bis(3-propanediyl-3,5,7-tris(2,1-ethanediyl-3,4-epoxycyclohexyl)-1,3,5,7-tetramethylcyclotetrasiloxanyl)polytetrahydrofuran

The invention also relates to the abovementioned, individually listednew cycloaliphatic epoxides per se.

The epoxides can be prepared in a simple manner. To prepare the epoxidesof type A without siloxanyl units, the cycloaliphatic alkenes obtainedby conventional etherification or esterification of di-, tri- or polyolswith cyclohexenecarboxylic acid or cyclohexenylmethanol are epoxidizedwith perbenzoic acid in suitable solvents, preferably in diethyl ether.When the reaction has ended, the mixture is washed several times withsodium hydroxide solution and dried over magnesium sulphate. Thevolatile constituents are distilled off in vacuo.

The epoxides of type A with siloxanyl units are prepared by two-stageconventional hydrosilylations: Compounds having two, three or moreterminal alkene functions are added to an excess of a siloxane having atleast two active hydrogen atoms and catalytic amounts of H₂PtCl₆,dissolved in a suitable solvent (e.g. hexane). When the reaction hasended, the mixture is freed from the platinum which has precipitatedout, washed once with water and dried over magnesium sulphate. In asecond hydrosilylation, the resulting di-, tri- orpolysiloxane-containing compound is dissolved in a suitable solvent,e.g. in toluene or alkanes, and heated with H₂PtCl₆ and vinylcyclohexeneepoxide. The mixture is freed from the platinum which has precipitatedout and washed once with water. The product is obtained by distillingoff the volatile constituents in vacuo.

To prepare epoxides of type B with terminal3-oxatricyclo[3.2.1.0^(2,4)]octanyl units, di- tri- orpoly(meth)acrylates are reacted with substituted (or unsubstituted)monomeric cyclopentadiene, thiophenes or furans under Lewis acidcatalysis (for example ZnCl₂ or AlCl₃) under normal pressure or in anautoclave to give the corresponding Diels-Alder products. The endocyclicdouble bond is epoxidized with perbenzoic acid in a suitable solvent,preferably in diethyl ether. When the reaction has ended, the mixture iswashed several times with sodium hydroxide solution and dried overmagnesium sulphate. The volatile constituents are distilled off invacuo.

In addition to the epoxides according to the invention, thepolymerizable compositions according to the invention can comprise, ascomponent (b), other low-viscosity epoxides. Low-viscosity epoxidesaccording to (b) can be, for example: 3,4-epoxycyclohexylmethyl3,4-epoxycyclohexanecarboxylate (U.S. Pat. No. 2,716,123),3,4-epoxy-6-methylcyclohexyl 3,4-epoxy-6-methylcyclohexanecarboxylate(U.S. Pat. No. 2,716,123) or related epoxides, vinylcyclohexenediepoxide (U.S. Pat. No. 2,948,688), dicyclopentadiene dioxide (U.S.Pat. No. 2,985,667), bis(3,4-epoxycyclohexylmethyl) adipate (U.S. Pat.No. 2,750,395, U.S. Pat. No. 2,863,881, U.S. Pat. No. 3,187,018),1,3,5,7-tetrakis(2,1-ethanediyl-3,4-epoxycyclohexyl)-1,3,5,7-tetramethylcyclotetrasiloxaneof the following formula:

1,3,5,7,9-pentakis(2,1-ethanediyl-3,4-epoxycyclohexyl)-1,3,5,7,9-pentamethylcyclopentasiloxane(U.S. Pat. No. 5,085,124) of the following formula:

and low molecular weight siloxanes functionalized with cycloaliphaticepoxides, for example1,1,3,3-tetramethyl-1,3-bis(ethanediyl-3,4-epoxycyclohexyl)disiloxane(EP-A-0 449 027, EP-A-0 574 265) of the following formula:

The low-viscosity epoxides according to component (b) are present in aconcentration of 0 to 80 wt. %, preferably 5 to 75 wt. %, in each casebased on the total weight of the composition.

Inorganic fillers according to component (c) can be the customary dentalfillers, for example quartz, ground, optionally X-ray-opaque, optionallyreactive glasses, sparingly soluble fluorides, such as CaF₂ or YF₃(EP-B-0 238 025), silica gels and pyrogenic silicic acid or granulesthereof. The compositions can also comprise, as fluoride-donatingconstituents, one or more water-soluble inorganic complex fluorides ofthe general formula A_(n)MF_(m), wherein A denotes a mono- or polyvalentcation, M denotes a metal of main group or sub-group III, IV or V, ndenotes an integer from 1 to 3 and m denotes an integer from 4 to 6(DE-A-4 445 266). The dental compositions contain these in aconcentration of 3 to 85 wt. %, preferably 5 to 75 wt. %, and inparticular 30 to 75 wt. %, based on the total composition. For betterincorporation into the polymer matrix, it maybe advantageous tohydrophobize the fillers and, if appropriate, the X-ray-opaqueadditives, such as YF₃. Customary hydrophobizing agents are silanes, forexample trimethoxyglycidylsilane. The maximum particle size of theinorganic fillers is preferably 20 μm, in particular 12 μm. Fillershaving an average particle size <7 μm are especially preferablyemployed.

Initiators according to component (d) of the compositions according tothe invention can be: Lewis or Broensted acids, or compounds whichliberate such acids, which initiate the polymerization, for example BF₃or ether adducts thereof (BF₃.THF, BF₃.Et₂O, etc.), AlCl₃, FeCl₃, HPF₆,HAsF₆, HSbF₆ or HBF₄, or substances which initiate the polymerizationafter irradiation by UV or visible light or by means of heat and/orpressure, such as e.g. (eta-6-cumene)(eta-5-cyclopentadienyl)ironhexafluorophosphate, (eta-6-cumene) (eta-5-cyclopentadienyl)irontetrafluoroborate, (eta-6-cumene)(eta-5-cyclopentadienyl)ironhexafluoroantimonate, substituted diaryliodonium salts andtriarylsulphonium salts. Accelerators which can be employed are peroxycompounds of the perester, diacyl peroxide, peroxydicarbonate andhydroperoxide type. Hydroperoxides are preferably used, and cumenehydroperoxide in an approximately 70 to 90% solution in cumene isemployed as the particularly preferred accelerator. The ratio ofphotoinitiator to cumene hydroperoxide can be varied within wide limitsfrom 1:0.001 to 1:10, but the ratio used is preferably 1:0.1 to 1:6, andparticularly preferably 1:0.5 to 1:4. The use of complexing agents, suchas, for example, oxalic acid, 8-hydroxyquinoline,ethylenediaminetetraacetic acid and aromatic polyhydroxy compounds, isalso possible. Retardants which can be added are bases, typicallytertiary amines. Component (d) is present in the composition accordingto the invention in an amount of 0.01 to 25 wt. %, preferably 0.01 to 20wt. %, based on the total weight of the composition.

Suitable auxiliaries according to component (e) can be, for example,stabilizers, pigments or diluents usually employed in the dental field.

The epoxide-containing polymerizable compositions according to theinvention are particularly suitable as materials for dental purposes,for example for the production of artificial teeth or temporaryprostheses, as coating compositions, for gluing substrates and as dentalfilling materials.

The polymerizable compositions according to the invention offer aparticular advantage in dental uses. The volume shrinkage of thecompositions according to the invention is far below the shrinkage ofknown compositions based on methacrylate monomers. As a result, forexample, the edge gap problem of filling materials can be largelyavoided. The dimensional stability and the storage stability of theepoxides according to the invention and of the polymerizablecompositions prepared therefrom is also of great advantage in the caseof precision model materials.

Compared with acrylate-based dental compositions, which have a veryshort setting time and therefore a sudden curing compared withepoxide-based compositions, the compositions according to the inventionshow a hardening which proceeds uniformly over a period of, for example,10 to 240 seconds. Stresses within the polymers formed are thus avoided.The compositions according to the invention therefore also have anoptimum processing time, before they reach their final hardness.

In addition to high compressive and flexural strengths, thepolymerizable compositions according to the invention surprisingly showhigh impact strengths, which is of outstanding importance for dentaluses.

The dental filling materials according to the invention moreover show asurprisingly good adhesion to the tooth substance. The epoxidesaccording to the invention furthermore are not mutagenic and areacceptable in respect of their cytotoxicity.

EXAMPLES OF THE SYNTHESIS OF THE MONOMERS ACCORDING TO THE INVENTION 1.Preparation of2,2-Bis[4,1-phenylenoxy-3,1-propanediyl-3,4-epoxycyclohexylcarboxylicAcid Ester]propylidene

100 g 2,2-bis(4-oxypropylhydroxyphenyl)propane are kept under refluxwith 85 g 4-cyclohexenecarboxylic acid in toluene for 6 hours. Thesolvent and excess 4-cyclohexenecarboxylic acid are distilled off. 161 g2,2-bis(4-oxypropylphenyl-3-cyclohexenylcarboxylate)propane remain andare added to 83 g perbenzoic acid in 500 ml diethyl ether. After areaction time of 8 hours, the mixture is washed several times with 10%sodium hydroxide solution and dried over magnesium sulphate. Thevolatile constituents are distilled off in vacuo.

2. Preparation ofbis(3,4-epoxycyclohexylethyl-tetramethyldisiloxanylpropoxymethyl)-tricyclo[5.2.1.0^(2,6)]decane

174 g tetramethyldisiloxane are initially introduced into 800 ml hexane,and 120 mg H₂PtCl₆ are added. 80 g tricyclo[5.2.1.0^(2,6)]decane-diallyl ether are added and the mixture is heated at 85° C.(b.p.) for 3 hours. The mixture is freed from the platinum which hasprecipitated out, washed once with water and dried over magnesiumsulphate. Hexane and volatile constituents are distilled off in vacuo.The resultingbis(tetramethyldisiloxanylpropoxymethyl)-tricyclo[5.2.1.0^(2,6)]decaneis dissolved in 200 ml hexane, 120 mg H₂PtCl₆ and 71 gvinyl-3,4-cyclohexene epoxide are added and the mixture is heated at 85°C. for 3 hours. The mixture is freed from the platinum which hasprecipitated out, washed once with water and dried over magnesiumsulphate. After the reaction mixture has been concentrated in vacuo, 202gbis(3,4-epoxycyclohexylethyl-tetramethyldisiloxanyl-propoxymethyl)-tricyclo[5.2.1.0^(2,6)]decaneare obtained.

3. Preparation ofα,ω-bis(3-propanediyl-3,5,7-tris(2,1-ethanediyl-3,4-epoxycyclohexyl)-1,3,5,7-tetramethylcyclotetrasiloxanyl)-polytetrahydrofuran

126 g α,ω-polytetrahydrofuran-600-diallyl ether are added to 151 g1,3,5,7-tetramethylcyclotetrasiloxane and 110 mg H₂PtCl₆ in 700 mlhexane. After 3 hours at 85° C., the platinum which has precipitated outis separated off and all the volatile constituents are distilled off invacuo.α,ω-Bis[3,5,7-tris(3,4-epoxycyclohexylethyl)-3-propyl-1,3,5,7-tetramethylcyclotetrasiloxanyl]-polytetrahydrofuranremains and is heated at 120° C. with 179 g vinylcyclohexene epoxide and130 mg H₂PtCl₆ in 800 ml toluene for 3 hours. The platinum which hasprecipitated out is separated off and all the volatile constituents aredistilled off in vacuo. 339 gα,ω-bis[3,5,7-tris(3,4-epoxycyclohexylethyl)-3-propyl-1,3,5,7-tetramethylcyclotetrasiloxanyl]-polytetrahydrofuranremain.

4. Preparation ofα,ω-bis(6-methyl-dioxatricyclo[3.2.1.0^(2,4)]octyl-6-carboxy)polyethyleneGlycol

85 g α,ω-polyethylene glycol-600-dimethacrylate are heated at 120° C.with 19 g furan in 300 ml toluene in an autoclave under 10 bar for 4hours. The volatile constituents are distilled off in vacuo.α,ω-Bis(3-methyl-7-oxabicyclo[2.2.1]heptyl-3-carboxy)polyethylene glycolremains and is added dropwise to a solution of 31 g perbenzoic acid in300 ml diethyl ether. After a reaction time of 8 hours, the mixture iswashed several times with 10% sodium hydroxide solution and dried overmagnesium sulphate. The volatile constituents are distilled off invacuo.

5. Preparation of1,1,1-tris[methanediyl-oxy-bis(ethanediyl-oxy)-methanediyl-3,4-epoxycyclohexyl]propane

168 g 1,1,1-tris(methanediyl-hydroxy-bis(ethanediyloxy)]propane areinitially introduced into 600 ml tetrahydrofuran. 178 g potassiumtert-butanolate are added in portions and the mixture is stirred at 30°C. for one hour. 277 g 3-cyclohexenylbromomethane, dissolved in 300 mltetrahydrofuran, are then added dropwise. The reaction mixture is heatedat 75° C. for 24 hours. The solvent is distilled off, the mixture issuspended in methyl tert-butyl ether and the precipitate is filteredoff. After aqueous extraction, 249 g1,1,1-tris[methanediyl-oxy-bis(ethanediyloxy)-methanediyl-3-cyclohexenyl]propaneremain and are dissolved in 500 ml diethyl ether. This solution is addedto 61 g perbenzoic acid in 400 ml diethyl ether and, after a reactiontime of 8 hours, the mixture is washed several times with 10% sodiumhydroxide solution. The mixture is dried over magnesium sulphate and thevolatile constituents are distilled off in vacuo.

Examples of Polymerizable Compositions

1. General Preparation of Polymerizable Compositions

1.1 One-component photo- or UV-curing systems

The preparation of the one-component compositions which can bepolymerized according to the invention is a two-stage process in whichhomogeneous premixing of all the constituents with the exception of thephotoinitiator takes place in the first stage. In a second stage, thephotoinitiator is kneaded homogeneously into the paste with exclusion oflight. When the epoxy resins according to the invention which have beenobtained in this way and can be processed have been mixed in completely,they are introduced into light-proof containers.

1.2 Two-component systems

The two-component compositions which can be polymerized according to theinvention are prepared by first preparing a homogeneously mixedcomponent A comprising the epoxide monomers, a filler content, theretardants, accelerators and the auxiliaries. A homogeneously mixedcomponent B comprising the initiator, diluent and a further fillercontent is furthermore prepared. Components A and B are introduced, forexample, into a double-cartridge system. The two-component compositioncan be processed directly by a static mixer on the cartridge system.

2. Use Examples

Example 1

Component A: A paste is kneaded from 17.6 parts by wt.α,ω-bis(3-propanediyl-3,5,7-tris(2,1-ethanediyl-3,4-epoxycyclohexyl)-1,3,5,7-tetramethylcyclotetrasiloxanyl)-ditetrahydrofuran,17.6 parts by wt. 3,4-epoxycyclohexylmethyl3,4-epoxycyclohexanecarboxylate and 64.7 parts by wt. of a silanized,pigmented quartz. A second component B comprises 32.8 parts by wt.polyethylene glycol, 4.7 parts by wt. BF₃.OEt₂ and 62.5 parts by wt. ofa silanized pigmented quartz. Pastes A and B are mixed in a ratio of 2:1via a static mixer. The composition cures within two minutes.

Example 2

A paste is kneaded from 18 parts by wt.bis(methanediyl-oxy-3,1-propanediyl-3,4-epoxycyclohexylcarboxylic acidester)-tricyclo[5.2.1.0^(2,6)]decane, 10 parts by wt.1,1,3,3-tetramethyl-1,3-bis(ethanediyl-3,4-epoxycyclohexyl)disiloxane,68.9 parts by wt. of a silanized pigmented quartz, 1.2 parts by wt.(eta-6-cumene)(eta-5-cyclopentadienyl)iron hexafluorophosphate and 1.8parts by wt. cumene hydroperoxide and is cured by irradiation with alamp (Elipar II light apparatus, ESPE Dental-Medizin GmbH & Co. KG,Germany) in the course of approx. 40 seconds.

Example 3

16.7 parts by wt.1,1,1-tris[methanediyl-oxy-1,3-propanediyl-1,1,3,3-tetramethyldisiloxanediyl-1,2-ethanediyl-3,4-epoxycyclohexyl]propane,4.5 parts by wt. 3,4-epoxycylcohexylmethyl3,4-epoxycyclohexanecarboxylate, 5.2 parts by wt.1,3,5,7-tetrakis(2,1-ethanediyl-3,4-epoxycyclohexyl)-1,3,5,7-tetramethylcyclotetrasiloxane,70.5 parts by wt. of a silanized pigmented quartz, 1.2 parts by wt.(eta-6-cumene)(eta-5-cyclopentadienyl)iron hexafluorophosphate and 1.9parts by wt. cumene hydroperoxide are kneaded to a paste, which is curedby irradiation with a lamp (Elipar II light apparatus, ESPEDental-Medizin GmbH & Co. KG, Germany) in the course of approx. 40seconds.

Example 4

18 parts by wt.2,2-bis[4,1-phenylenoxy-3,1-propanediyl-3,4-epoxycyclohexylcarboxylicacid ester]propylidene, 13 parts by wt. 3,4-epoxycyclohexylmethyl3,4-epoxycyclohexanecarboxylate, 65.4 parts by wt. of a silanizedpigmented quartz, 1.5 parts by wt.(eta-6-cumene)(eta-5-cyclopentadienyl)iron hexafluorophosphate and 2.1parts by wt. cumene hydroperoxide are kneaded to a paste, which is curedby irradiation with a lamp (Elipar II light apparatus, ESPEDental-Medizin GmbH & Co. KG, Germany) in the course of approx. 40seconds.

Example 5

Comparison paste, commercially obtainable dental composition

Ex- Ex- Ex- Ex- Ex- ample ample ample ample ample 5 (comp- 1 2 3 4arison) Compressive 388 331 361 355 385 strength [MPa] Flexural strength151 131 121 141 118 [MPa] (ISO 4049) Volume shrinkage [%] 1.3 0.8 0.71.0 2.2

What is claimed is:
 1. Polymerizable dental composition comprising (a) 3to 80 wt. % of an epoxide or a mixture of epoxides of the generalformula:

 in which, for type A: if n=2 Z denotes a cycloaliphatic or aromaticradical having 1 to 22 carbon atoms or a combination of these radicals,wherein one or more carbon atoms can be replaced by O, C═O, —O(C═O)—,SiR₂ and/or NR, or an aliphatic radical having 0 to 22 carbon atoms,wherein one or more carbon atoms can be replaced by O, C═O, —O(C═O)—, NRor SiR₂, wherein at least one carbon atom must be replaced by SiR₂, andwherein R is an aliphatic radical having 1 to 7 carbon atoms, whereinone or more carbon atoms can be replaced by O, C═O and/or —O(O═O)—, ifn>2 Z denotes an aliphatic, cycloaliphatic or aromatic radical having 0to 22 carbon atoms or a combination of these radicals, wherein one ormore carbon atoms can be replaced by O, C═O, —O(C═O)—, SiR₂ and/or NRand wherein R is an aliphatic radical having 1 to 7 carbon atoms,wherein one or more carbon atoms can be replaced by O, C═O and/or—O(C═O)—, and in which, for type B: Z denotes an aliphatic,cycloaliphatic or aromatic radical having 0 to 22 carbon atoms or acombination of these radicals, wherein one or more carbon atoms can bereplaced by O, C═O, —O(C═O)—, SiR₂ and/or NR and wherein R is analiphatic radical having 1 to 7 carbon atoms, wherein one or more carbonatoms can be replaced by O, C═O and/or —O(C═O)—, and in which, for typeA and type B: A denotes an aliphatic, cycloaliphatic or aromatic radicalhaving 1 to 18 carbon atoms or a combination of these radicals, whereinone or more carbon atoms can be replaced by O, C═O, —O(C═O)—, SiR₂and/or NR, wherein R is an aliphatic radical having 1 to 7 carbon atoms,in which one or more carbon atoms can be replaced by O, C═O and/or—O(C═O)—, B₁, B₂, D and E independently of one another denote a hydrogenatom or an aliphatic radical having 1 to 9 carbon atoms, wherein one ormore carbon atoms can be replaced by O, C═O, —O(C═O)—, SiR₂ and/or NR,wherein R is an aliphatic radical having 1 to 7 carbon atoms, in whichone or more carbon atoms can be replaced by O, C═O and/or —O(C═O)—, ndenotes 2-7, m denotes 1-10, p denotes 1-5, q denotes 1-5 and x denotesCH₂, S or O, (b) 0 to 80 wt. % of an epoxide or a mixture of epoxideswhich differ from (a), (c) 3 to 85 wt. % of fillers, (d) 0.01 to 25 wt.% of initiators and retardants or accelerators, (e) 0 to 25 wt. % ofauxiliaries, the percentage data in each case being based on the totalweight of the composition wherein the initiators (d) are Lewis orBroensted acids, or compounds which liberate such acids, which initiatepolymerization, or substances which initiate polymerization afterirradiation by UV or visible light, or by means of heat and/or pressure,in contact with a tooth.
 2. Polymerizable composition as claimed inpatent claim 1, characterized in that it comprises, as component (a),one or more of the following epoxides: i)2,2-bis[4,1-phenylenoxy-3,1-propanediyl-3,4-epoxycyclohexylcarboxylicacid ester]propylidene

ii)2,2-bis[4,1-phenylenoxy-3,1-propanediyl-oxy-methanediyl-3,4-epoxycyclohexyl]propylidene

iii)2,2-bis[3,4-epoxycyclohexylmethanediyl(4,1-phenylenoxy-3,1-propylcarboxylicacid ester)]propylidene

iv)2,2-bis[4,1-phenylenoxy-3,1-propanediyl-1,1,3,3-tetramethyldisiloxanyl-1,2-ethanediyl-3,4-epoxycyclohexyl]propylidene

v)2,2-bis{4,1-phenylenoxy-3,1-propanediyl-3-oxatricyclo[3.2.1.0^(2,4)]octyl-6-carboxy}propylidene

iv)2,2-bis{4,1-phenylenoxy-3,1-propanediyl-3,8-dioxatricyclo[3.2.1.0^(2,4)]octyl-6-carboxy}propylidene

vii)2,2-bis{4,1-phenylenoxy-3,1-propanediyl-[3,5,7-tris(ethanediyl-3,4-epoxycyclohexyl)-1,3,5,7-tetramethylcyclotetrasiloxanyl]}propylidene

viii) bis[methanediyl-oxy-3,1-propanediyl-3,4-epoxycyclohexylcarboxylicacid ester]tricyclo[5.2.1.0^(2,6)]decane

ix)bis[methanediyl-oxy-3,1-propanediyl-oxy-methanediyl-3,4-epoxycyclohexyl]tricyclo[5.2.1.0^(2,6)]decane

x) bis[3,4-epoxycyclohexylmethanediyl-propanecarboxylicacid-1-oxy-methanediyl]tricyclo[5.2.1.0^(2,6)]decane

xi)bis(methanediyl-oxy-3,1-propanediyl-1,1,3,3-tetramethyldisiloxanediyl-1,2-ethanediyl-3,4-epoxycyclohexyl)tricyclo[5.2.1.0^(2,6)]decane

xii)bis{methanediyl-oxy-3,1-propanediyl-3-oxatricyclo[3.2.1.0^(2,6)]octyl-6-carboxyl}tricyclo[5.2.1.0^(2,6)]decane

xiii)bis{methanediyl-oxy-3,1-propanediyl-3,8-dioxatricyclo[3.2.1.0^(2,6)]octyl-6-carboxyl}tricyclo[5.2.1.0^(2,6)]decane

xiv)bis(methanediyl-oxy-(3-propanediyl-3,5,7-tris(2,1-ethanediyl-3,4-epoxycyclohexyl)-1,3,5,7-tetramethylcyclotetrasiloxanyl)tricyclo[5.2.1.0^(2,6)]decane

xv) 1,1,1-tris[methanediyl-oxy-methanediyl-3,4-epoxycyclohexyl]propane

xvi)1,1,1-tris[methanediyl-oxy-1,3-propanediyl-1,1,3,3-tetramethyldisiloxanediyl-1,2-ethanediyl-3,4-epoxycyclohexyl]propane

xvii)1,1,1-tris{methanediyl-3-oxatricyclo[3.2.1.0^(2,4)]octyl-6-carboxy}propane

xviii)1,1,1-trist{methanediyl-3,8-dioxatricyclo[3.2.1.0^(2,4)]octyl-6-carboxy}propane

xix)1,1,1-tris[methanediyl-oxy-3,1-propanediyl-3,5,7-tris(2,1-ethanediyl-3,4-epoxycyclohexyl)-1,3,5,7-tetramethylcyclotetrasiloxanyl]propane

xx)1,1,1-tris[methanediyl-oxy-bis(ethanediyloxy)-3,4-epoxycyclohexylcarboxylicacid ester]propane

xxi)1,1,1-tris[methanediyl-oxy-bis(ethanediyloxy)-methanediyl-3,4-epoxycyclohexyl]propane

xxii)1,1,1-tris[methanediyl-oxy-bis(ethanediyloxy)-propanediyl-1,1,3,3-tetramethyldisiloxanyl-1,2-ethanediyl-3,4-epoxycyclohexyl]propane

xxii)1,1,1-tris{methanediyl-oxy-bis(ethanediyloxy)-3-oxatricyclo[3.2.1.0^(2,4)]octyl-6-carboxy}propane

xxiv)1,1,1-tris{methanediyl-oxy-bis(ethanediyloxy)-3,8-dioxatricyclo[3.2.1.0^(2,4)]octyl-6-carboxy}propane

xxv)1,1,1,1-tris[methanediyl-oxy-bis(ethanediyloxy)-propanediyl-3,5,7-tris(2,1-ethanediyl-3,4-epoxycyclohexyl)-1,3,5,7-tetramethylcycloletrasiloxanyl]propane

xxvi)α,ω-bis[3,4-epoxycyclohexylethanediyl-1,1,3,3-tetramethyldisiloxanyl-3,1-propanediyl]polytetrahydrofuran

xxvii)α,ω-bis{3-oxatricyclo[3.2.1.0^(2,4)]octyl-6-carboxy}polytetrahydrofuran

xxviii)α,ω-bis{3,8-dioxatricyclo[3.2.1.0^(2,4)]octyl-6-carboxy}polytetrahydrofuran

xxix)α,ω-bis(3-propanediyl-3,5,7-tris(2,1-ethanediyl-3,4-epoxycyclohexyl)-1,3,5,7-tetramethylcyclotetrasiloxanyl)polytetrahydrofuran


3. Polymerizable composition as claimed in patent claim 1, characterizedin that it comprises, as the low-viscosity epoxide according tocomponent b) 3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate,3,4-epoxy-6-methylcyclohexyl 3,4-epoxy-6-methyl cyclohexanecarboxylate,dicyclopentadiene dioxide, bis(3,4-epoxycyclohexylmethyl)adipate,1,3,5,7-tetrakis(2,1-ethanediyl-3,4-epoxycyclohexyl)-1,3,5,7-tetramethylcyclotetrasiloxane,1,3,5,7,9-pentakis(2,1-ethanediyl-3,4-epoxycyclohexyl)-1,3,5,7,9-pentamethylcyclopentasiloxane,1,1,3,3-tetramethyl-1,3-bis(ethanediyl-3,4-epoxycyclohexyl)disiloxaneand/or low molecular weight siloxanes functionalized with cycloaliphaticepoxides.
 4. Polymerizable composition according to at least one ofpatent claim 1, characterized in that it comprises, as fillers accordingto component c), quartz, ground glasses, silica gels or silicic acids orgranules thereof.
 5. Polymerizable composition according to at least oneof patent claim 1, characterized in that it comprises, as retardants,accelerators and/or initiators, Lewis acids or Broensted acids orcompounds from which such as acids are formed by irradiation with UVlight or visible light or by heat and/or pressure.
 6. Polymerizablecomposition according to at least one of patent claim 1, characterizedin that it comprises, as auxiliaries, diols, diluents, stabilizers,inhibitors and/or pigments.
 7. Polymerizable composition according to atleast claim 1, comprising A a paste comprising the epoxides ofcomponents (a) and (b), a portion or all of the filler of component (c),if appropriate retardants or accelerators according to component (d) andif appropriate auxiliaries of component (e), and, spatially separatedtherefrom, B a paste comprising an initiator according to component (d),if appropriate a portion of the filler of component (c) and ifappropriate auxiliaries according to component (e).
 8. The polymerizabledental composition of claim 1, wherein for type A, if n=2 and if Zdenotes a cycloaliphatic, aromatic or alaphatic radical, then theradical has 1 to 18 carbon atoms.
 9. The polymerizable dentalcomposition of claim 1, wherein for type A, if n>2 and if Z denotes acycloaliphatic, aromatic or alaphatic radical, then the radical has 1 to18 carbon atoms.
 10. The polymerizable dental composition of claim 1,wherein for type B, if Z denotes a cycloaliphatic, aromatic or alaphaticradical, then the radical has 1 to 18 carbon atoms.
 11. An epoxideselected from the group consisting of: i)2,2-bis[4,1-phenylenoxy-3,1-propanediyl-3,4-epoxycyclohexylcarboxylicacid ester]propylidene

ii)2,2-bis[4,1-phenylenoxy-3,1-propanediyl-oxy-methanediyl-3,4-epoxycyclohexyl]propylidene

iii)2,2-bis[3,4-epoxycyclohexylmethanediyl(4,1-phenylenoxy-3,1-propylcarboxylicacid ester)]propylidene

iv)2,2-bis[4,1-phenylenoxy-3,1-propanediyl-1,1,3,3-tetramethyldisiloxanyl-1,2-ethanediyl-3,4-epoxycyclohexyl]propylidene

v)2,2-bis{4,1-phenylenoxy-3,1-propanediyl-3-oxatricyclo[3.2.1.0^(2,4)]octyl-6-carboxy}propylidene

vi)2,2-bis{4,1-phenylenoxy-3,1-propanediyl-3,8-dioxatricyclo[3.2.1.0^(2,4)]octyl-6-carboxy}propylidene

vii)2,2-bis{4,1-phenylenoxy-3,1-propanediyl-[3,5,7-tris(ethanediyl-3,4-epoxycyclohexyl)-1,3,5,7-tetramethylcyclotetrasiloxanyl]}propylidene

viii) bis[methanediyl-oxy-3,1-propanediyl-3,4-epoxycyclohexylcarboxylicacid ester]tricyclo[5.2.1.0^(2,6)]decane

ix)bis[methanediyl-oxy-3,1-propanediyl-oxy-methanediyl-3,4-epoxycyclohexyl]tricyclo[5.2.1.0^(2,6)]decane

x) bis[3,4-epoxycyclohexylmethanediyl-propanecarboxylicacid-1-oxy-methanediyl]tricyclo[5.2.1.0^(2,6)]decane

xi)bis(methanediyl-oxy-3,1-propanediyl-1,1,3,3-tetramethyldisiloxanediyl-1,2-ethanediyl-3,4-epoxycyclohexyl)tricyclo[5.2.1.0^(2,6)]decane

xii)bis{methanediyl-oxy-3,1-propanediyl-3-oxatricyclo[3.2.1.0^(2,6)]octyl-6-carboxyl}tricyclo[5.2.1.0^(2,6)]decane

xiii)bis{methanediyl-oxy-3,1-propanediyl-3,8-dioxatricyclo[3.2.1.0^(2,6)]octyl-6-carboxyl}tricyclo[5.2.1.0^(2,6)]decane

xiv)bis(methanediyl-oxy-(3-propanediyl-3,5,7-tris(2,1-ethanediyl-3,4-epoxycyclohexyl)-1,3,5,7-tetramethylcyclotetrasiloxanyl)-tricyclo[5.2.1.0^(2,6)]decane

xv) 1,1,1-tris[methanediyl-oxy-methanediyl-3,4-epoxycyclohexyl]propane

xvi)1,1,1-tris[methanediyl-oxy-1,3-propanediyl-1,1,3,3-tetramethyldisiloxanediyl-1,2-ethanediyl-3,4-epoxycyclohexyl]propane

xvii)1,1,1-tris{methanediyl-3-oxatricyclo[3.2.1.0^(2,4)]octyl-6-carboxy}propane

xviii)1,1,1-tris{methanediyl-3,8-dioxatricyclo[3.2.1.0^(2,4)]octyl-6-carboxy}propane

xix)1,1,1-tris[methanediyl-oxy-3,1-propanediyl-3,5,7-tris(2,1-ethanediyl-3,4-epoxycyclohexyl)-1,3,5,7-tetramethylcyclotetrasiloxanyl]propane

xx)1,1,1-tris[methanediyl-oxy-bis(ethanedilyloxy)-3,4-epoxycyclohexylcarboxylicacid ester]propane

xxi)1,1,1-tris[methanediyl-oxy-bis(ethanediyloxy)-methanediyl-3,4-epoxycyclohexyl]propane

xxii)1,1,1-tris[methanediyl-oxy-bis(ethanediyloxy)-propanediyl-1,1,3,3-tetramethyldisiloxanyl-1,2-ethanediyl-3,4-epoxycyclohexyl]propane

xxiii)1,1,1-tris{methanediyl-oxy-bis(ethanediyloxy)-3-oxatricyclo[3.2.1.0^(2,4)]octyl-6-carboxy}propane

xxiv)1,1,1-tris{methanediyl-oxy-bis(ethanediyloxy)-3,8-dioxatricyclo[3.2.1.0^(2,4)]octyl-6-carboxy}propane

xxv)1,1,1-tris[methanediyl-oxy-bis(ethanediyloxy)-propanediyl-3,5,7-tris(2,1-ethanediyl-3,4-epoxycyclohexyl)-1,3,5,7-tetramethylcyclotetrasiloxanyl]propane

xxvi)α,ω-bis[3,4-epoxycyclohexylethanediyl-1,1,3,3-tetramethyldisiloxanyl-3,1-propanediyl]polytetrahydrofuran

xxvii)α,ω-bis{3-oxatricyclo[3.2.1.0^(2,4)]octyl-6-carboxy}polytetrahydrofuran

xxviii) α,ω-bis{3,8-dioxatricyclo[3.2.1.0^(2,4)]octyl-6-carboxy}polytetrahydrofuran

xxix)α,ω-bis(3-propanediyl-3,5,7-tris(2,1-ethanediyl-3,4-epoxycyclohexyl)-1,3,5,7-tetramethylcyclotetrasiloxanyl)polytetrahydrofuran